Add Oracle WebLogic 14.1.2 support

[jethropickering-support]

Is your feature request related to a problem?

The supported technologies matrix lists Oracle WebLogic 12.2 as the only version covered by the integration test suite. On WebLogic 14.1.2.0.0 the agent cannot reach APM Server at all. Reverting back to 12c fixes the issue.

The agent starts and the tracer reaches RUNNING, then every outbound HTTP call fails because WebLogic's own HTTP client returns a null socket factory:

WARN  co.elastic.apm.agent.report.ApmServerHealthChecker - Elastic APM server http://<apm-server>:8200/ is not available (Cannot invoke "javax.net.SocketFactory.createSocket()" because the return value of "weblogic.net.http.HttpClient.getSocketFactory()" is null)
java.lang.NullPointerException: Cannot invoke "javax.net.SocketFactory.createSocket()" because the return value of "weblogic.net.http.HttpClient.getSocketFactory()" is null
	at weblogic.net.http.HttpClient.openServer(HttpClient.java:403) ~[com.oracle.weblogic.net.jar:14.1.2.0]
	at weblogic.net.http.HttpClient.New(HttpClient.java:329) ~[com.oracle.weblogic.net.jar:14.1.2.0]
	at weblogic.net.http.HttpURLConnection.connect(HttpURLConnection.java:368) ~[com.oracle.weblogic.net.jar:14.1.2.0]
	at weblogic.net.http.HttpURLConnection.getInputStream(HttpURLConnection.java:770) ~[com.oracle.weblogic.net.jar:14.1.2.0]
	at weblogic.net.http.SOAPHttpURLConnection.getInputStream(SOAPHttpURLConnection.java:42) ~[com.oracle.weblogic.net.jar:14.1.2.0]
	at co.elastic.apm.agent.report.HttpUtils.consumeAndClose(HttpUtils.java:62) ~[elastic-apm-agent-1.56.0.jar:1.56.0]
	at co.elastic.apm.agent.report.ApmServerClient.executeForAllUrls(ApmServerClient.java:306) ~[elastic-apm-agent-1.56.0.jar:1.56.0]
	at co.elastic.apm.agent.report.ApmServerHealthChecker.call(ApmServerHealthChecker.java:67) ~[elastic-apm-agent-1.56.0.jar:1.56.0]

Two things distinguish this from prior reports:

• It occurs on plain HTTP, not HTTPS.
• It is a different failure from Weblogic exception on agent startup : Class not Found weblogic.security.SSL.jsseadapter.JaSSLContextImpl #2409, which was an HTTPS ClassNotFoundException for weblogic.security.SSL.jsseadapter.JaSSLContextImpl. That was fixed by Set context CL for reliable weblogic connection #3870, and 1.56.0 includes the fix, so the socket factory returning null is not covered by it.

Remaining on 12.2 is not always an available option.

Describe the solution you'd like

Add Oracle WebLogic 14.1.2 to the tested matrix, so the agent connects to APM Server on that version without workarounds.

Describe alternatives you've considered

• -DUseSunHttpHandler=true makes WebLogic defer to the JDK's Sun HTTP handler instead of its own, bypassing the failing class. Reported in earlier WebLogic cases as a global flag that also alters WebLogic's own HTTP behaviour, so a trade-off rather than a clean workaround. Untested against this failure.
• elastic.apm.delay_agent_premain_ms was tried during the earlier WebLogic investigation and did not reliably help there.
• HTTPS rather than HTTP. A distinct WebLogic code path, and the one agent-side defect known to affect it (Weblogic exception on agent startup : Class not Found weblogic.security.SSL.jsseadapter.JaSSLContextImpl #2409) is fixed in 1.56.0. Untested here, and gated on the deployment having TLS available.

Additional context

Environment where this was reproduced:

WebLogic	14.1.2.0.0, production mode, managed server started via NodeManager
JDK	Oracle JDK 21
Agent	1.56.0
APM Server	self-managed, plain HTTP
OS	Linux (RHEL 8)